1. Technical Field of the Invention
The present invention relates to a gas supply apparatus for supplying a predetermined kind of gas (e.g., carbon dioxide gas) to body cavities of a subject to be medically treated, and more particularly, to a gas supply apparatus which supplies gas to different body cavities, such as an abdominal cavity and a luminal cavity, at different pressures, respectively.
2. Related Art
In recent years, laparoscopic surgeries are performed for curative treatment without opening an abdominal cavity, for the purpose of mitigating invasion on a subject to be examined. In a laparoscopic surgery, a first trocar for guiding an endoscope for observation and a second trocar for guiding a treatment tool to a site to be treated, for example, are punctured into an abdomen of a subject. Also, in a laparoscopic surgery, treatment or the like is performed observing both a site to be treated and a treatment tool that has been inserted through an insertion hole of the second trocar, by using an endoscope inserted into an abdominal cavity through an insertion hole of the first trocar.
In such a laparoscopic surgery, an abdominal insufflation apparatus is used for injecting carbon dioxide gas, for example, as an abdominal insufflation gas into an abdominal cavity for purposes of retaining a visual field for the endoscope and a space for manipulating the treatment tool.
For luminal cavities, such as a stomach and a large intestine, an endoscope and a treatment tool as mentioned above are also used for diagnosis and treatment. In effecting medical treatment, including diagnosis and treatment, in luminal cavities, such as a stomach and a large intestine by an endoscopic observation, a gas, such as air as a luminal cavity gas is injected into the luminal cavity for purposes of retaining a visual field for the endoscope and a space for manipulating the treatment tool. Air, which is generally supplied into a luminal cavity by a gas supply pump, may be replaced by carbon dioxide gas.
Recently, a new approach may be taken in a laparoscopic surgery by inserting an endoscope into a luminal cavity to internally and externally specify a site to be treated for effecting treatment. In this case as well, air, for example, may be supplied from an endoscope inserted into a luminal cavity to inflate the luminal cavity.
However, when air is supplied into a luminal cavity as described above, as air is less likely to be absorbed by a living organism, the luminal cavity may possibly remain being inflated and may make it difficult to retain a necessary space for laparoscopic surgery. Accordingly, there has been a need for use of an endoscope CO2 regulator (hereinafter referred to as an ECR), a device for sending a gas such as carbon dioxide gas which is easily absorbed by living organisms, such as a large intestine.
However, arranging conventional surgical equipment for endoscopic surgery by providing an ECR, results in placing a set of the abdominal insufflation apparatus and a CO2 container, separately from a set of the ECR and a CO2 container. This results in increasing variety of pieces of peripheral medical equipment, which are to be accommodated in a plurality of carts, making movement a bothersome labor.
In the prior art equipment described above, two pieces of equipment, i.e. an abdominal insufflation apparatus and an ECR, have to be separately provided, which arises problems of cumbersome and complicated preparation and of spatial inefficiency. Further, when pieces of equipment are separately set up, erroneous connections tend to occur, e.g., connecting a luminal cavity tube to a supply fitting of an abdominal insufflation apparatus, or connecting an abdominal cavity tube to a supply fitting of an ECR.